Field of the Invention
The present invention relates to an ophthalmological apparatus that optically inspects a subject's eye.
Description of the Related Art
The ophthalmological apparatus includes an ophthalmological imaging device for acquiring an image of a subject's eye, and an ophthalmological measuring device for measuring characteristics of the subject's eye.
Examples of the ophthalmological imaging device are as follows: an optical coherence tomograph that acquires a tomographic image by using optical coherence tomography (OCT); a fundus camera for photographing a fundus; a scanning laser ophthalmoscope (SLO) that acquires an image of a fundus by using laser scanning with a confocal optical system; a slit lamp that acquires an image by using slit light to cut off an optical section of a cornea; and the like.
In addition, examples of the ophthalmological measuring device are as follows: an inspection device for refraction of eye (a refraction meter, or a keratometer) that measures refraction characteristics of a subject's eye; a tonometer; a specular microscope that acquires characteristics of a cornea (such as cornea thickness, and cell distribution); a wavefront analyzer that acquires aberration information on a subject's eye by using a Hartmann-Shack sensor; and the like.
There is known a conventional ophthalmological apparatus that has a plurality of photographing modes, such as a color photographing mode, and a fluorescent photographing mode, to perform photographing suitable for a purpose of inspection (refer to Japanese Patent Application Laid-Open No. 2008-289579, for example). In this kind of ophthalmological apparatus, setting of various optical systems (such as an illumination optical system, and a photographic optical system) is generally changed in accordance with a photographing mode selected.
In the ophthalmological apparatus, a vision fixation target is projected on a subject's eye before photographing for vision fixation of the subject's eye. The term, “vision fixation”, means that the vision fixation target is projected toward the subject's eye to keep a line of sight direction of the subject's eye constant. In photographing of a fundus, a “vision fixation direction (vision fixation position)” can be considered as a “photographing portion (portion of interest)” on a premise that vision fixation is reliably performed. The term, “portion of interest”, means a portion on which an inspector focuses during observation, such as an optic disk, and a macula lutea, in ophthalmology.